Antibodies against the dinitroaminophenyl (DNAP) haptenic group were raised in outbred CFY rats using HSA or LPS as carrier. Antibodies isolated by immunoadsorbent techniques were resolved into fractions representing distinct isotypes, and the resulting fractions were tested for avidity. Subclass IgG2a was found to contain antibodies of an avidity index lower than those of other IgG subclasses or IgM. IgG2a was the only isotype detected when DNAP-LPS was used for immunization. Complexes containing defined isotypes were compared for their capacity to activate homologous complement. IgG1 type antibody-containing complexes displayed a low complement activating capacity compared with those containing IgG2b, IgG2c or IgG2a. The latter subclass when complexed with antigen can thus induce complement-dependent processes in spite of a low avidity. Insoluble complexes of IgG antibodies were rapidly solubilized in rat serum (CRA phenomenon), except those containing predominantly IgG2c.
|Number of pages||6|
|Publication status||Published - Oct 9 1981|
ASJC Scopus subject areas
- Immunology and Allergy